Image processing method and apparatus

ABSTRACT

In an image processing method, a direction transforming process is performed on an image signal representing an image and in accordance with information giving specifics about an image recording technique. In cases where a marker pattern, which is represented by a marker signal, is to be appended to the image represented by the image signal, the direction and the appending position of the marker signal are determined in accordance with the information giving specifics about the image recording technique. The marker signal is appended to the image signal in accordance with the thus determined direction and the thus determined appending position of the marker signal. The marker signal is thus appended to the image signal in an appropriate state in accordance with the specifics about the image recording technique.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This is a Continuation of application Ser. No. 09/568,161 filedMay 10, 2000, the disclosure of which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to an image processing method andapparatus, in which a direction transforming process for reversingand/or rotating an image signal representing an image of an object isperformed in accordance with information giving specifics about an imagerecording technique, such as the direction from which the image of theobject, e.g. a patient, is recorded, and the orientation of the objectin the image recording operation. This invention also relates to arecording medium, on which a program for causing a computer to executethe image processing method has been recorded and from which thecomputer is capable of reading the program.

[0004] 2. Description of the Prior Art

[0005] It has been proposed by the applicant to use stimulable phosphorsin radiation image recording and reproducing systems. Specifically, aradiation image of an object, such as a human body, is recorded on asheet provided with a layer of the stimulable phosphor (hereinafterreferred to as a stimulable phosphor sheet). The stimulable phosphorsheet, on which the radiation image has been stored, is then exposed tostimulating rays, such as a laser beam, which cause it to emit light inproportion to the amount of energy stored thereon during its exposure tothe radiation. The light emitted by the stimulable phosphor sheet, uponstimulation thereof, is photoelectrically detected and converted into anelectric image signal. The image signal is then subjected to imageprocessing, such as gradation processing, and the thus obtainedprocessed image signal is used for the reproduction of the radiationimage of the object as a visible image on a recording material.

[0006] In the radiation image recording and reproducing systemsdescribed above, the operation for recording a radiation image of anobject is performed with one of various image recording techniques. Forexample, in cases where a radiation image of the chest of a patient isto be recorded, radiation may be irradiated to the patient from the backside of the patient or from the abdomen side of the patient. Also, inthe image recording operation, the patient may stand facing thestimulable phosphor sheet or may stand facing the side opposite to thestimulable phosphor sheet. The image signal having been obtained byreading out the recorded radiation image is subjected to a process forreversing or rotating the radiation image in accordance with the imagerecording technique, which was employed in the image recordingoperation, and the image signal having been obtained from the process isutilized for reproducing the radiation image as a visible image. By wayof example, in cases where the image recording operation is performed,in which the patient stands facing the stimulable phosphor sheet andradiation is irradiated to the patient from the back side of thepatient, the radiation image shown in FIG. 2A is obtained, in which apattern of the heart is embedded on the left side when the radiationimage is seen from the direction of irradiation of the radiation.However, when the radiation image is to be used for making a diagnosisof an illness, it is necessary that the heart pattern is located on theright side as the person, who sees the image, stands facing the image.Therefore, in such cases, as illustrated in FIG. 2B, a process forreversing the right and left sides of the image represented by theoriginal image signal is performed on the original image signal, and areversed image signal is thereby obtained. The reversed image signal isthen utilized for reproducing a visible image. In this manner, areproduced image, in which the heart pattern is located on the rightside as the person, who sees the image, stands facing the image, can beobtained.

[0007] An operation for recording a radiation image of an object isoften performed by the utilization of a marker for representing thedirection from which the image of the object is recorded, theorientation of the object, e.g. a patient, in the image recordingoperation, or the like. The marker utilized in the image recordingoperation is formed from a metal, such as lead, which does not transmitradiation. For example, in cases where a radiation image of the chest ofa human body is to be obtained, an L-shaped marker may be attached to anupper left corner area of the stimulable phosphor sheet, and the imagepattern of the marker may be recorded together with the object image onthe stimulable phosphor sheet. In such cases, the radiation image shownin FIG. 3A is obtained, in which the L-shaped marker pattern is embeddedat the upper left corner area when the radiation image is seen from thedirection of irradiation of the radiation. When the radiation imageshown in FIG. 3A is reproduced as a visible image, the right and leftsides of the image represented by the original image signal arereversed, and the image shown in FIG. 3B is obtained. In such cases,when a person sees the reproduced image, since the L-shaped markerpattern has been reversed, the person can easily recognize that theright and left sides of the image have been reversed.

[0008] Instead of the marker pattern being recorded together with theobject image, it may be considered to append a digital marker signalrepresenting the marker pattern to the image signal representing theradiation image. In cases where the marker signal is thus appended tothe image signal, a radiation image can be obtained, in which the markerpattern has been appended to a desired position. Also, a marker patternhaving an arbitrary shape can be embedded in the radiation image.

[0009] However, as described above, the image signal, to which themarker signal is to be appended, is often subjected to the directiontransforming process through reversion or rotation in accordance withthe information giving specifics about the image recording technique.Therefore, if the marker signal is directly appended to the imagesignal, which has been obtained from the direction transforming process,the problems described below will occur. Specifically, the problems willoccur in that, for example, as illustrated in FIG. 19, in cases wherethe marker signal is the one representing the L-shaped marker pattern,the image represented by the image signal has been transformed indirection, but the L-shaped marker pattern is appended to the image inthe form having not been transformed in direction. Therefore, theperson, who sees the radiation image, will misunderstand that theradiation image is the one having not been transformed in direction, andthere is the risk that an incorrect diagnosis, or the like, will bemade.

SUMMARY OF THE INVENTION

[0010] The primary object of the present invention is to provide animage processing method, wherein a marker signal is capable of beingappended to an image signal in an appropriate state in accordance withspecifics about an image recording technique.

[0011] Another object of the present invention is to provide anapparatus for carrying out the image processing method.

[0012] A further object of the present invention is to provide arecording medium, on which a program for causing a computer to executethe image processing method has been recorded and from which thecomputer is capable of reading the program.

[0013] The present invention provides a first image processing method,in which a direction transforming process is performed on an imagesignal representing an image and in accordance with information givingspecifics about an image recording technique, and in which a markerpattern represented by a marker signal is appended to the imagerepresented by the image signal, the method comprising the steps of:

[0014] i) determining a direction of the marker signal and an appendingposition of the marker signal in accordance with the information givingspecifics about the image recording technique, and

[0015] ii) appending the marker signal to the image signal in accordancewith the thus determined direction of the marker signal and the thusdetermined appending position of the marker signal.

[0016] The term “specifics about an image recording technique” as usedherein means the direction of incidence of radiation in the imagerecording operation, the orientation (positioning) of an object, such asa patient, the orientation of a stimulable phosphor sheet for storing aradiation image, and the like.

[0017] The term “direction transforming process” as used herein meansthe process for reversing and/or rotating the image signal, such that animage seen from a desired direction can be obtained when the image isreproduced from the image signal having been obtained from the process.The term “rotation” as used herein means the operation for rotating theimage, which is represented by the image signal, by a desired anglearound, for example, the center of gravity on the image. The term“reversion” as used herein means the operation for reversing the image,which is represented by the image signal, symmetrically with respect to,for example, a certain axis.

[0018] In the first image processing method in accordance with thepresent invention, the direction of the marker signal and the appendingposition of the marker signal are determined in accordance with theinformation giving specifics about the image recording technique.Specifically, the direction of the marker signal and the appendingposition of the marker signal are determined such that the direction andthe appending position of a marker pattern embedded in a radiationimage, which has been obtained by performing an image recordingoperation by use of a marker and which has then been subjected to adirection transforming process, and the direction and the appendingposition of the marker pattern embedded in the radiation image, whichhas been reproduced from the image signal (after being subjected to thedirection transforming process) that is appended with the marker signal,may coincide with each other.

[0019] The term “appending a marker signal to an image signal” as usedherein means the operation for replacing the image signal components ofthe image signal, which correspond to the position to be appended withthe marker pattern, by the marker signal, or the operation for appendingthe marker signal to the image signal as an overlay signal for the imagesignal. The image signal, to which the marker signal is to be appended,may be the one after being subjected to the direction transformingprocess. Alternatively, the image signal, to which the marker signal isto be appended, may be the one before being subjected to the directiontransforming process.

[0020] The first image processing method in accordance with the presentinvention should preferably be modified such that a size of the markersignal is altered in accordance with a size of the image, which isrepresented by the image signal, and/or a read-out density, with whichthe image signal was obtained.

[0021] Also, the first image processing method in accordance with thepresent invention should preferably be modified such that a markersignal representing a marker pattern having a size adapting to a size ofthe image, which is represented by the image signal, and/or a read-outdensity, with which the image signal was obtained, is selected from aplurality of marker signals, which represent marker patterns havingdifferent sizes and having been prepared previously, and

[0022] the direction and the appending position of the thus selectedmarker signal are determined.

[0023] Further, the first image processing method in accordance with thepresent invention should preferably be modified such that, in caseswhere the image signal components of the image signal, which correspondto the position in the vicinity of the appending position of the markersignal, take signal values (for example, in the cases of 8 bits, 255 orvalues close to 255) approximately identical with the signal value ofthe marker signal, the signal value of the marker signal is altered(such that the marker pattern becomes perceptible), and/or the signalvalues of the image signal components of the image signal, which imagesignal components correspond to the position in the vicinity of theappending position of the marker signal, are altered. The marker signalmay then be appended to the image signal.

[0024] The present invention also provides a second image processingmethod, in which a direction transforming process is performed on animage signal representing an image and in accordance with informationgiving specifics about an image recording technique, and in which amarker pattern represented by a marker signal is appended to the imagerepresented by the image signal, the method comprising the steps of:

[0025] i) performing the direction transforming process on the imagesignal,

[0026] ii) displaying an image, which is represented by the image signalhaving been subjected to the direction transforming process, togetherwith a pointer, which indicates an arbitrary position on the image, ondisplaying means,

[0027] iii) altering the direction of the marker signal in accordancewith the information giving specifics about the image recordingtechnique,

[0028] iv) altering the shape of the pointer to a shape of a markerpattern, which is represented by the altered marker signal,

[0029] v) altering the position of the marker pattern on the image inaccordance with a pointer position altering instruction, and

[0030] vi) appending the marker signal to the image signal in accordancewith a marker pattern appending instruction given at a desired positionon the image displayed on the displaying means.

[0031] The second image processing method in accordance with the presentinvention should preferably be modified such that a size of the markersignal is altered in accordance with a size of the image, which isrepresented by the image signal, and/or a read-out density, with whichthe image signal was obtained.

[0032] Also, the second image processing method in accordance with thepresent invention should preferably be modified such that a markersignal representing a marker pattern having a size adapting to a size ofthe image, which is represented by the image signal, and/or a read-outdensity, with which the image signal was obtained, is selected from aplurality of marker signals, which represent marker patterns havingdifferent sizes and having been prepared previously, and

[0033] the direction of the thus selected marker signal is altered.

[0034] Further, as in the aforesaid first image processing method inaccordance with the present invention, the second image processingmethod in accordance with the present invention should preferably bemodified such that, in cases where the image signal components of theimage signal, which correspond to the position in the vicinity of theappending position of the marker signal, take signal valuesapproximately identical with the signal value of the marker signal, thesignal value of the marker signal is altered (such that the markerpattern becomes perceptible), and/or the signal values of the imagesignal components of the image signal, which image signal componentscorrespond to the position in the vicinity of the appending position ofthe marker signal, are altered. The marker signal may then be appendedto the image signal.

[0035] The present invention further provides a first image processingapparatus, which is provided with direction transforming means forperforming a direction transforming process on an image signalrepresenting an image and in accordance with information givingspecifics about an image recording technique, and in which a markerpattern represented by a marker signal is appended to the imagerepresented by the image signal, the apparatus comprising:

[0036] i) determination means for determining a direction of the markersignal and an appending position of the marker signal in accordance withthe information giving specifics about the image recording technique,and

[0037] ii) marker signal appending means for appending the marker signalto the image signal in accordance with the thus determined direction ofthe marker signal and the thus determined appending position of themarker signal.

[0038] The first image processing apparatus in accordance with thepresent invention should preferably be modified such that thedetermination means alters a size of the marker signal in accordancewith a size of the image, which is represented by the image signal,and/or a read-out density, with which the image signal was obtained.

[0039] Also, the first image processing apparatus in accordance with thepresent invention should preferably be modified such that the apparatusfurther comprises storage means for storing a plurality of markersignals, which represent marker patterns having different sizes andhaving been prepared previously, and selection means for selecting amarker signal representing a marker pattern having a size adapting to asize of the image, which is represented by the image signal, and/or aread-out density, with which the image signal was obtained, theselection being made from the plurality of the marker signals, whichrepresent the marker patterns having different sizes and have beenstored in the storage means, and

[0040] the determination means determines the direction and theappending position of the thus selected marker signal.

[0041] Further, the first image processing apparatus in accordance withthe present invention should preferably further comprise signal valuealtering means for operating such that, in cases where a signal value ofthe marker signal and signal values of image signal components of theimage signal, which image signal components correspond to the positionin the vicinity of the appending position of the marker signal,approximately coincide with each other, the signal value altering meansalters the signal value of the marker signal and/or the signal values ofthe image signal components of the image signal, which image signalcomponents correspond to the position in the vicinity of the appendingposition of the marker signal.

[0042] The present invention still further provides a second imageprocessing apparatus, which is provided with direction transformingmeans for performing a direction transforming process on an image signalrepresenting an image and in accordance with information givingspecifics about an image recording technique, the apparatus comprising:

[0043] i) displaying means for displaying an image, which is representedby the image signal having been subjected to the direction transformingprocess performed by the direction transforming means, together with apointer, which indicates an arbitrary position on the image,

[0044] ii) marker signal altering means for altering a direction of amarker signal, which represents a marker pattern to be appended to theimage represented by the image signal, in accordance with theinformation giving specifics about the image recording technique,

[0045] iii) pointer altering means for altering the shape of the pointerto a shape of a marker pattern, which is represented by the alteredmarker signal,

[0046] iv) position altering means for altering the position of themarker pattern on the image in accordance with a pointer positionaltering instruction, and

[0047] v) marker signal appending means for appending the marker signalto the image signal in accordance with a marker pattern appendinginstruction given at a desired position on the image displayed on thedisplaying means.

[0048] The second image processing apparatus in accordance with thepresent invention should preferably be modified such that thedetermination means alters a size of the marker signal in accordancewith a size of the image, which is represented by the image signal,and/or a read-out density, with which the image signal was obtained.

[0049] Also, the second image processing apparatus in accordance withthe present invention should preferably be modified such that theapparatus further comprises storage means for storing a plurality ofmarker signals, which represent marker patterns having different sizesand having been prepared previously, and selection means for selecting amarker signal representing a marker pattern having a size adapting to asize of the image, which is represented by the image signal, and/or aread-out density, with which the image signal was obtained, theselection being made from the plurality of the marker signals, whichrepresent the marker patterns having different sizes and have beenstored in the storage means, and

[0050] the marker signal altering means alters the direction of the thusselected marker signal.

[0051] Further, the second image processing apparatus in accordance withthe present invention should preferably further comprise signal valuealtering means for operating such that, in cases where a signal value ofthe marker signal and signal values of image signal components of theimage signal, which image signal components correspond to the positionin the vicinity of the appending position of the marker signal,approximately coincide with each other, the signal value altering meansalters the signal value of the marker signal and/or the signal values ofthe image signal components of the image signal, which image signalcomponents correspond to the position in the vicinity of the appendingposition of the marker signal.

[0052] The present invention also provides a recording medium, on whicha program for causing a computer to execute the first image processingmethod in accordance with the present invention has been recorded andfrom which the computer is capable of reading the program.

[0053] The present invention further provides a recording medium, onwhich a program for causing a computer to execute the second imageprocessing method in accordance with the present invention has beenrecorded and from which the computer is capable of reading the program.

[0054] With the first image processing method and apparatus inaccordance with the present invention, in cases where the markerpattern, which is represented by the marker signal, is to be appended tothe image represented by the image signal, the direction of the markersignal and the appending position of the marker signal are determined inaccordance with the information giving specifics about the imagerecording technique. At this time, the direction of the marker signaland the appending position of the marker signal are determined such thatthe direction and the appending position of a marker pattern embedded ina radiation image, which has been obtained by performing an imagerecording operation by use of a marker, and the direction and theappending position of the marker pattern embedded in the radiation imagehaving been reproduced from the image signal appended with the markersignal may coincide with each other. Therefore, in accordance with thedirection transforming process performed on the image signal, the markerpattern represented by the marker signal can be appended to the imagerepresented by the image signal in the same manner as that in the caseswhere the image recording operation is performed by use of a marker.Accordingly, the problems can be prevented from occurring in that theperson, who sees the radiation image, misunderstands the reversion ofthe radiation image or the direction of rotation of the radiation imageand makes an incorrect diagnosis, or the like.

[0055] With the second image processing method and apparatus inaccordance with the present invention, the image, which is representedby the image signal having been subjected to the direction transformingprocess, is displayed on the displaying means. Also, the direction ofthe marker signal is altered in accordance with the information givingspecifics about the image recording technique. Further, the shape of thepointer, which is displayed on the displaying means, is altered to theshape of the marker pattern, which is represented by thedirection-altered marker signal. Thereafter, the position of the markerpattern on the image is altered in accordance with the pointer positionaltering instruction. Further, the marker signal is appended to theimage signal in accordance with the marker pattern appending instructiongiven at a desired position on the image displayed on the displayingmeans. Therefore, the image in the state in which the marker pattern isappended can be confirmed on the displaying means, and the markerpattern appending position can be determined easily.

[0056] With the first image processing method and apparatus inaccordance with the present invention and the second image processingmethod and apparatus in accordance with the present invention, whereinthe size of the marker signal is altered in accordance with the size ofthe image, which is represented by the image signal, and/or the read-outdensity, with which the image signal was obtained, the marker patternadapting to the size of the image, which is represented by the imagesignal, and/or the read-out density, with which the image signal wasobtained, can be displayed on the image. Therefore, the marker patternwhich is easy to see can be obtained.

[0057] With the first image processing method and apparatus inaccordance with the present invention and the second image processingmethod and apparatus in accordance with the present invention, themarker signal representing the marker pattern having the size adaptingto the size of the image, which is represented by the image signal,and/or the read-out density, with which the image signal was obtained,may be selected from a plurality of marker signals, which representmarker patterns having different sizes and having been preparedpreviously, and the direction and the appending position of the thusselected marker signal may be determined, or the direction of the thusselected marker signal may be altered. In such cases, the marker patternhaving the size adapting to the size of the image, which is representedby the image signal, and/or the read-out density, with which the imagesignal was obtained, can be displayed on the image. Therefore, themarker pattern which is easy to see can be obtained.

[0058] With the first image processing method and apparatus inaccordance with the present invention and the second image processingmethod and apparatus in accordance with the present invention, in caseswhere the signal value of the marker signal and the signal values ofimage signal components of the image signal, which image signalcomponents correspond to the position in the vicinity of the appendingposition of the marker signal, approximately coincide with each other,the signal value of the marker signal and/or the signal values of theimage signal components of the image signal, which image signalcomponents correspond to the position in the vicinity of the appendingposition of the marker signal, may be altered. In such cases, forexample, when a white marker pattern is appended to a white region inthe image, the marker pattern can be kept easy to see.

BRIEF DESCRIPTION OF THE DRAWINGS

[0059]FIG. 1 is a schematic block diagram showing a radiation imageoutput system, in which a first embodiment of the image processingapparatus in accordance with the present invention is employed,

[0060]FIG. 2A is an explanatory view showing an example of a radiationimage reproduced from an image signal,

[0061]FIG. 2B is an explanatory view showing a radiation image obtainedby reversing the radiation image shown in FIG. 2A,

[0062]FIG. 3A is an explanatory view showing an example of a radiationimage reproduced from an image signal, which has been obtained byperforming an image recording operation by use of a marker,

[0063]FIG. 3B is an explanatory view showing a radiation image obtainedby reversing the radiation image shown in FIG. 3A,

[0064]FIG. 4 is an explanatory view showing an example of how a markersignal is appended to an image signal in the first embodiment of theimage processing apparatus in accordance with the present invention,

[0065]FIG. 5 is a flow chart showing how the first embodiment of theimage processing apparatus in accordance with the present inventionoperates,

[0066]FIG. 6 is a schematic block diagram showing a radiation imageoutput system, in which a second embodiment of the image processingapparatus in accordance with the present invention is employed,

[0067]FIG. 7 is a flow chart showing how the second embodiment of theimage processing apparatus in accordance with the present inventionoperates,

[0068]FIGS. 8A, 8B, and 8C are explanatory views showing how a markersignal is appended in the second embodiment,

[0069]FIG. 9 is a schematic block diagram showing a radiation imageoutput system, in which a third embodiment of the image processingapparatus in accordance with the present invention is employed,

[0070]FIG. 10 is a flow chart showing how the third embodiment of theimage processing apparatus in accordance with the present inventionoperates,

[0071]FIG. 11 is a schematic block diagram showing a radiation imageoutput system, in which a fourth embodiment of the image processingapparatus in accordance with the present invention is employed,

[0072]FIG. 12 is a schematic block diagram showing a radiation imageoutput system, in which a fifth embodiment of the image processingapparatus in accordance with the present invention is employed,

[0073]FIG. 13 is a flow chart showing how the fifth embodiment of theimage processing apparatus in accordance with the present inventionoperates,

[0074]FIG. 14 is a schematic block diagram showing a radiation imageoutput system, in which a sixth embodiment of the image processingapparatus in accordance with the present invention is employed,

[0075]FIG. 15 is a schematic block diagram showing a radiation imageoutput system, in which a seventh embodiment of the image processingapparatus in accordance with the present invention is employed,

[0076]FIG. 16A is an explanatory view showing a different example of aradiation image reproduced from an image signal,

[0077]FIG. 16B is an explanatory view showing a radiation image obtainedby rotating and reversing the radiation image shown in FIG. 16A,

[0078]FIG. 17A is an explanatory view showing a different example of aradiation image reproduced from an image signal, which has been obtainedby performing an image recording operation by use of a marker,

[0079]FIG. 17B is an explanatory view showing a radiation image obtainedby rotating and reversing the radiation image shown in FIG. 17A,

[0080]FIG. 18 is an explanatory view showing an example of how a markersignal is appended to an image signal, and

[0081]FIG. 19 is an explanatory view showing a radiation image obtainedwhen a marker signal is directly appended to an image signal, which hasbeen obtained from a reversing process.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0082] The present invention will hereinbelow be described in furtherdetail with reference to the accompanying drawings.

[0083]FIG. 1 is a schematic block diagram showing a radiation imageoutput system, in which a first embodiment of the image processingapparatus in accordance with the present invention is employed. Asillustrated in FIG. 1, the radiation image output system comprises animage forming apparatus 1 for performing an image recording operationfor recording a radiation image of an object, and obtaining an imagesignal S0 representing the radiation image. The radiation image outputsystem also comprises an image processing apparatus 2 for performing adirection transforming process on the image signal S0 and in accordancewith information giving specifics about the image recording technique,appending a marker signal to the image signal S0, and performing imageprocessing, such as gradation processing, processing in the frequencydomain, or the like, in order to obtain a processed image signal S2. Theradiation image output system further comprises an image outputapparatus 3 for reproducing a visible image as a print from theprocessed image signal S2.

[0084] The image forming apparatus 1 comprises image recording means 11,which is provided with a radiation source 16 and a sheet support section18 for supporting a stimulable phosphor sheet 17. In the image recordingmeans 11, radiation is produced by the radiation source 16 andirradiated to an object, and the radiation carrying image information ofthe object is irradiated to the stimulable phosphor sheet 17. In thismanner, a radiation image of the object is stored on the stimulablephosphor sheet 17. The image forming apparatus 1 also comprises imageread-out means 12 for photoelectrically reading out the radiation imagefrom the stimulable phosphor sheet 17, on which the radiation image hasbeen stored, and thereby obtaining the image signal S0 representing theradiation image. The image forming apparatus 1 further comprises anidentification terminal (IDT) 13, from which various kinds ofinformation, such as the information representing the name of a patient,the information representing the title of an examination, and theinformation giving specifics about an image recording technique, areinputted. In the image recording means 11, the object (in this case, apatient) stands facing the stimulable phosphor sheet 17, the radiationis irradiated to the patient from the back side of the patient, and theradiation image of the chest of the patient is recorded on thestimulable phosphor sheet 17. The radiation image is thenphotoelectrically read out by the image read-out means 12 from thestimulable phosphor sheet 17, on which the radiation image has beenstored, and the image signal S0 representing the radiation image of theobject is thereby obtained. At the time of the image recordingoperation, pieces of information (hereinbelow referred to as the IDinformation T), such as the information representing the name of thepatient, the information representing the title of the examination, andthe information giving specifics about the image recording technique,are inputted from the IDT 13. In this embodiment, the information, whichrepresents that the patient stood facing the stimulable phosphor sheet17 and the radiation was irradiated to the patient from the back side ofthe patient in the image recording operation, is employed as theinformation giving specifics about the image recording technique.

[0085] The image processing apparatus 2 comprises a memory 21 forstoring a marker signal M. The image processing apparatus 2 alsocomprises determination means 22 for determining the direction and theappending position of a marker pattern, which is represented by themarker signal M, in accordance with the ID information T having beenreceived from the IDT 13 of the image forming apparatus 1. The imageprocessing apparatus 2 further comprises marker signal appending means23 for appending the marker signal M to the image signal S0. The imageprocessing apparatus 2 still further comprises direction transformingmeans 24 for performing a direction transforming process on the imagesignal S0, which has been appended with the marker signal M, and inaccordance with the ID information T, and thereby obtaining adirection-transformed image signal S1. The image processing apparatus 2also comprises processing means 25 for performing image processing, suchas gradation processing and processing in the frequency domain, on thedirection-transformed image signal SI and thereby obtaining theprocessed image signal S2.

[0086] In the determination means 22, the direction and the appendingposition of the marker signal M with respect to the image signal S0 aredetermined in the manner described below. Specifically, the radiationimage represented by the image signal S0 obtained from the image formingapparatus 1 is the one obtained by performing the image recordingoperation, in which the patient stood facing the stimulable phosphorsheet 17, the radiation was irradiated from the back side of thepatient, and the radiation image of the patient was thereby stored onthe stimulable phosphor sheet 17. When the radiation image is reproducedfrom the image signal S0, the radiation image shown in FIG. 2A isobtained. However, when the radiation image is to be used for making adiagnosis of an illness, as illustrated in FIG. 2B, the radiation imageshould be reproduced such that the heart pattern is located on the rightside as the person, who sees the image, stands facing the image.Therefore, in the direction transforming means 24, the directiontransforming process is performed on the image signal S0 and inaccordance with the ID information T, such that the right and left sidesof the radiation image shown in FIG. 2A, which is represented by theimage signal S0, are reversed with respect to an axis extendingvertically along the plane of the sheet of FIG. 2A. In this manner, thedirection-transformed image signal S1 representing the radiation imageshown in FIG. 2B, in which the heart pattern is located on the rightside as the person, who sees the image, stands facing the image, isobtained.

[0087] In the image recording operation, an L-shaped marker may beattached to a position on the stimulable phosphor sheet 17, whichposition corresponds to a position in the vicinity of the left shoulderof the patient, in order to indicated that the position is the leftside. In such cases, as illustrated in FIG. 3A, an L-shaped markerpattern is embedded in the image represented by the image signal S0.Also, as illustrated in FIG. 3B, in the image represented by thedirection-transformed image signal S1, which is obtained from theprocess performed by the direction transforming means 24 for reversingthe right and left sides of the image, the marker pattern having thereversed L-shape is embedded. Therefore, the medical doctor, who seesthe image shown in FIG. 3B, can confirm that the marker pattern has beenreversed, and can thereby recognize that the entire image has beenreversed. Accordingly, in the determination means 22, the direction andthe appending position of the marker signal M with respect to theradiation image represented by the image signal S0 are determined suchthat, when the image signal S0 is reversed by the direction transformingmeans 24, the image as shown in FIG. 3B can be obtained, in which themarker pattern having the reversed L-shape is embedded. Also, the markersignal appending means 23 appends the marker signal M to the imagesignal S0 in accordance with the thus determined direction and the thusdetermined appending position of the marker signal M. Specifically, asillustrated in FIG. 4, the marker signal M is appended to the imagesignal S0 such that the L-shaped marker pattern, which is represented bythe marker signal M, is embedded in the non-reversed form at a positionin the vicinity of the image pattern of the left shoulder of the patientin the image represented by the image signal S0. The appending of themarker signal M to the image signal S0 may be performed by replacing theimage signal components of the image signal S0, which correspond to theposition to be appended with the marker pattern, by the marker signal M,or by appending the marker signal M to the image signal S0 as an overlaysignal for the image signal S0.

[0088] In the manner described above, the marker signal M is appended tothe image signal S0. Therefore, as illustrated in FIG. 3B, when avisible image is reproduced from the direction-transformed image signalS1, which has been obtained by reversing the image signal S0 having beenappended with the marker signal M, the reproduced image can be obtainedin the same manner as that in the cases where the image recordingoperation was performed by use of a marker.

[0089] How the first embodiment of the image processing apparatus inaccordance with the present invention operates will be describedhereinbelow. FIG. 5 is a flow chart showing how the first embodiment ofthe image processing apparatus in accordance with the present inventionoperates. Firstly, in a step S1, the image forming apparatus 1 performsthe image recording operation for recording the radiation image of theobject, such as the patient, and forms the image signal S0 representingthe radiation image. At this time, in a step S2, the ID information Trepresenting the name of the patient, the examination number, specificsabout the image recording technique, and the like, is inputted from theIDT 13. The image signal S0 and the ID information T are fed into theimage processing apparatus 2. In a step S3, the determination means 22of the image processing apparatus 2 reads the marker signal M from thememory 21 and determines the direction and the appending position of themarker signal M in accordance with the ID information T. In a step S4,the marker signal appending means 23 appends the marker signal M to theimage signal S0 as illustrated in FIG. 4. In cases where the markersignal M is thus appended to the image signal S0, when a visible imageis reproduced from the image signal S0 appended with the marker signalM, the radiation image shown in FIG. 3A is obtained.

[0090] In a step S5, the image signal S0 appended with the marker signalM is fed into the direction transforming means 24, and the directiontransforming process is performed by the direction transforming means 24in accordance with the ID information T. From the direction transformingprocess, the direction-transformed image signal S1 is obtained. In caseswhere a visible image is reproduced from the direction-transformed imagesignal S1, the radiation image shown in FIG. 3B is obtained. In a stepS6, the thus obtained direction-transformed image signal S1 is fed intothe processing means 25, and the image processing, such as the gradationprocessing or processing in the frequency domain, is performed by theprocessing means 25 on the direction-transformed image signal S1. Theprocessed image signal S2 is obtained from the image processing.Thereafter, in a step S7, the processed image signal S2 is fed into theimage output apparatus 3 and utilized for reproducing a visible image tobe used in making a diagnosis.

[0091] As described above, in the first embodiment, the direction andthe appending position of the marker signal M are determined inaccordance with the ID information T representing variouscharacteristics of the image recording operation. In accordance with thedetermined direction and the determined appending position of the markersignal M, the marker signal M is appended to the image signal S0.Therefore, in accordance with the direction transforming processperformed on the image signal S0, the marker signal M can be appended tothe image signal S0 in the same manner as that in the cases where theimage recording operation is performed by use of a marker. Accordingly,the problems can be prevented from occurring in that the person, whosees the radiation image, misunderstands the reversion of the radiationimage or the direction of rotation of the radiation image and makes anincorrect diagnosis, or the like.

[0092] A second embodiment of the image processing apparatus inaccordance with the present invention will be described hereinbelow.FIG. 6 is a schematic block diagram showing a radiation image outputsystem, in which a second embodiment of the image processing apparatusin accordance with the present invention is employed. In FIG. 6, similarelements are numbered with the same reference numerals with respect toFIG. 1. Also, in FIG. 6, as for the image forming apparatus 1, only theimage read-out means 12 and the IDT 13 are illustrated.

[0093] With reference to FIG. 6, an image processing apparatus 2′comprises the memory 21 for storing the marker signal M, and markersignal altering means 30 for altering the direction of the marker signalM in accordance with the ID information T, which has been received fromthe IDT 13 of the image forming apparatus 1, and thereby obtaining adirection-altered marker signal M′. The image processing apparatus 2′also comprises direction transforming means 24′ for performing thedirection transforming process on the image signal S0 in accordance withthe ID information T and thereby obtaining a direction-transformed imagesignal S10. The image processing apparatus 2′ further comprisesdisplaying means 31, which displays the image represented by thedirection-transformed image signal S10 and which may be constituted of aCRT monitor, a liquid crystal monitor, or the like. The image processingapparatus 2′ still further comprises input means 32, from which variousinstructions are given to the displaying means 31 and which may beconstituted of a mouse device, a keyboard, or the like. The imageprocessing apparatus 2′ also comprises pointer altering means 33 foraltering the shape of a pointer, which is displayed on the displayingmeans 31, to the shape of the marker pattern represented by thedirection-altered marker signal M′. The image processing apparatus 2′further comprises marker signal appending means 23′ for appending thedirection-altered marker signal M′ to the image signal S0 in accordancewith a marker pattern appending instruction F, which is specified fromthe input means 32 as will be described later, and thereby obtaining animage signal S11. The image processing apparatus 2′ still furthercomprises processing means 25′ for performing the image processing, suchas the gradation processing or processing in the frequency domain, onthe image signal S11 and thereby obtaining a processed image signal S12.

[0094] How the second embodiment of the image processing apparatus inaccordance with the present invention operates will be describedhereinbelow. FIG. 7 is a flow chart showing how the second embodiment ofthe image processing apparatus in accordance with the present inventionoperates. FIGS. 8A, 8B, and 8C show how the images are displayed on thedisplaying means 31. Firstly, in a step S11, the image forming apparatus1 performs the image recording operation for recording the radiationimage of the object, such as the patient, and forms the image signal S0representing the radiation image. At this time, in a step S12, the IDinformation T representing the name of the patient, the examinationnumber, specifics about the image recording technique, and the like, isinputted from the IDT 13. The image signal S0 and the ID information Tare fed into the image processing apparatus 2′. In a step S13, thedirection transforming means 24′ of the image processing apparatus 2′performs the direction transforming process on the image signal S0, andthe direction-transformed image signal S10 is thereby obtained. In astep S14, the image represented by the direction-transformed imagesignal S10 is displayed on the displaying means 31.

[0095] By way of example, the radiation image represented by the imagesignal S0 obtained from the image forming apparatus 1 may be the oneobtained by performing the image recording operation, in which thepatient stood facing the stimulable phosphor sheet 17, the radiation wasirradiated from the back side of the patient, and the radiation image ofthe patient was thereby stored on the stimulable phosphor sheet 17. Insuch cases, when the radiation image is reproduced from the image signalS0, the radiation image shown in FIG. 2A is obtained. In the directiontransforming means 24′ of the image processing apparatus 2′, thedirection transforming process is performed on the image signal S0 andin accordance with the ID information T, such that the right and leftsides of the radiation image shown in FIG. 2A, which is represented bythe image signal S0, are reversed with respect to an axis extendingvertically along the plane of the sheet of FIG. 2A. In this manner, thedirection-transformed image signal S1 representing the radiation imageshown in FIG. 2B, in which the heart pattern is located on the rightside as the person, who sees the image, stands facing the image, isobtained. Also, the radiation image shown in FIG. 2B is displayed on thedisplaying means 31.

[0096] In a step S15, the marker signal altering means 30 reads themarker signal M from the memory 21 and alters the direction of themarker signal M in accordance with the ID information T. In this manner,the direction-altered marker signal M′ is obtained. In a step S16, thepointer altering means 33 alters the shape of the pointer, which isdisplayed on the displaying means 31, into the shape of the markerpattern represented by the direction-altered marker signal M′. Forexample, in cases where the marker pattern represented by the markersignal M is the one having the L-shape, the marker pattern representedby the direction-altered marker signal M′ has the reversed L-shape,whose right and left sides have been reversed. Therefore, in cases wherethe pointer has the arrow shape as illustrated in FIG. 8A, as a resultof the processing performed in the step S16, as illustrated in FIG. 8B,the shape of the pointer is altered into the reversed L-shape, whoseright and left sides have been reversed.

[0097] The mouse device of the input means 32 is then operated to shiftthe position of the pointer on the image displayed on the displayingmeans 31. As a result, the marker pattern to be appended moves. In astep S17, a judgment is made as to whether the marker pattern appendinginstruction has been or has not been given at a desired appendingposition by the input means 32. In cases where it has been judged thatthe marker pattern appending instruction has been given, the markerpattern appending instruction F is inputted into the marker signalappending means 23′.

[0098] In a step S18, the marker signal appending means 23 appends thedirection-altered marker signal M′ to the direction-transformed imagesignal S10 in accordance with the marker pattern appending instructionF, and the image signal S11 is thereby obtained. When the image isreproduced from the image signal S11, the image shown in FIG. 8C isobtained. In a step S19, the image signal S11 having thus been appendedwith the direction-altered marker signal M′ is fed into the processingmeans 25′, and the image processing, such as the gradation processing orthe processing in the frequency domain, is performed on the image signalS11. In this manner, the processed image signal S12 is obtained. In astep S20, the processed image signal S12 is fed into the image outputapparatus 3 and is utilized for reproducing a visible image. The visibleimage is used for making a diagnosis.

[0099] As described above, with the second embodiment, the imagerepresented by the direction-transformed image signal S10 is displayedon the displaying means 31, and the shape of the pointer displayed onthe displaying means 31 is altered into the shape of the marker pattern,which is represented by the direction-altered marker signal M′. Also, inaccordance with the marker pattern appending instruction given at adesired position on the image, the direction-altered marker signal M′ isappended to the direction-transformed image signal S10. Therefore, theimage in the state in which the marker pattern is appended can beconfirmed on the displaying means 31, and the marker pattern appendingposition can be determined easily.

[0100] A third embodiment of the image processing apparatus inaccordance with the present invention will be described hereinbelow.FIG. 9 is a schematic block diagram showing a radiation image outputsystem, in which a third embodiment of the image processing apparatus inaccordance with the present invention is employed. In FIG. 9, similarelements are numbered with the same reference numerals with respect toFIG. 1. Also, in FIG. 9, as for the image forming apparatus 1, only theimage read-out means 12 and the IDT 13 are illustrated.

[0101] With reference to FIG. 9, in an image processing apparatus 102,the determination means 22 alters the size of the marker signal M inaccordance with the size of the image, which is represented by the imagesignal S0, and/or the read-out density information H, with which theimage signal S0 was obtained in the image read-out means 12. Also, thedetermination means 22 determines the direction and the appendingposition of the marker pattern in accordance with the image recordingtechnique. Further, the marker signal appending means 23 appends themarker signal M to the image signal S0. Therefore, the image signal S0and/or read-out density information H is fed from the image read-outmeans 12 into the determination means 22.

[0102] In the determination means 22, the size of the marker signal M isaltered in the manner described below. In this embodiment, it is assumedthat the marker signal M has a size adapting to an image having apredetermined size or to an image having been obtained with apredetermined read-out density. Firstly, alteration of the size of themarker signal M in accordance with the size of the image signal S0 isperformed in the manner described below. Specifically, the ratio betweenthe length of the longer side of the image, which is represented by theimage signal S0, and the length of the longer side of the image havingthe predetermined size is calculated. in accordance with the calculatedratio, the size of the marker signal M is altered. For example, theimage having the predetermined size may have a 800×600 size, the imagerepresented by the image signal S0 may have a 1,200×900 size, and themarker pattern represented by the marker signal M may have a 40×30 size.In such cases, the size of the marker signal M is altered to a size 1.5times as large as the original size, i.e. to a 60×45 size.

[0103] Alteration of the size of the marker signal M in accordance withthe read-out density information H is performed in the manner describedbelow. Specifically, the size of the marker signal M is altered inaccordance with the ratio between the pixel size in the image, which isread out with the predetermined read-out density, and the pixel size inthe image, which is represented by the image signal S0, such that thesize of the marker pattern on the image may be kept as a predeterminedsize regardless of the pixel size. For example, in cases where thepredetermined read-out density is 600 dpi and the read-out density, withwhich the image signal S0 was obtained, is 1,200 dpi, the pixel size inthe image represented by the image signal S0 is one half of the pixelsize in the image, which is read out with the predetermined read-outdensity. Therefore, in cases where the size of the marker pattern is a40×30 size, the size of the marker signal M is altered to a size twotimes as large as the original size, i.e. to a 80×60 size, such that thesize of the marker pattern may not be altered on the image representedby the image signal S0.

[0104] In cases where the size of the marker signal M is to be alteredin accordance with both the size of the image, which is represented bythe image signal S0, and the read-out density information H, the size ofthe marker signal M may be altered in accordance with the ratio betweenthe length of the longer side of the image, which is represented by theimage signal S0, and the length of the longer side of the image havingthe predetermined size, and in accordance with the ratio between thepixel size in the image, which is read out with the predeterminedread-out density, and the pixel size in the image, which is representedby the image signal S0.

[0105] How the third embodiment of the image processing apparatus inaccordance with the present invention operates will be describedhereinbelow. FIG. 10 is a flow chart showing how the third embodiment ofthe image processing apparatus in accordance with the present inventionoperates. Firstly, in a step S21, the image forming apparatus 1 performsthe image recording operation for recording the radiation image of theobject, such as the patient, and forms the image signal S0 representingthe radiation image. At this time, in a step S22, the ID information Trepresenting the name of the patient, the examination number, specificsabout the image recording technique, and the like, is inputted from theIDT 13. The image signal S0, the ID information T, and the read-outdensity information H representing the read-out density, with which theimage signal S0 was obtained, are fed into the image processingapparatus 102. In a step S23, the determination means 22 of the imageprocessing apparatus 102 reads the marker signal M from the memory 21and alters the size of the marker signal M in accordance with the sizeof the image, which is represented by the image signal S0, and/or theread-out density information H. Also, in a step S24, the determinationmeans 22 determines the direction and the appending position of themarker signal M in accordance with the ID information T. In a step S25,the marker signal appending means 23 appends the marker signal M to theimage signal S0.

[0106] In steps S26, S27, and S28, as in the steps S5, S6, and S7 in thefirst embodiment described above, the direction transforming process,the image processing, and reproduction of a visible image from theprocessed image signal S2 are performed.

[0107] As described above, with the third embodiment, the size of themarker signal M is altered in accordance with the size of the image,which is represented by the image signal S0, and/or the read-outdensity, with which the image signal S0 was obtained. Therefore, themarker pattern adapting to the size of the image, which is representedby the image signal, and/or the read-out density, with which the imagesignal was obtained, can be displayed on the image. Therefore, themarker pattern which is easy to see can be obtained.

[0108] As in an image processing apparatus 102′ which constitutes afourth embodiment and is shown in FIG. 11, the image signal S0 and/orthe read-out density information H fed from the image read-out means 12may be inputted into the marker signal altering means 30 of the imageprocessing apparatus 2′ shown in FIG. 6. Also, in the marker signalaltering means 30, as in the determination means 22 in the thirdembodiment of FIG. 9, the size of the marker signal M may be altered inaccordance with the size of the image, which is represented by the imagesignal S0, and/or the read-out density, with which the image signal S0was obtained.

[0109] A fifth embodiment of the image processing apparatus inaccordance with the present invention will be described hereinbelow.FIG. 12 is a schematic block diagram showing a radiation image outputsystem, in which a fifth embodiment of the image processing apparatus inaccordance with the present invention is employed. In FIG. 12, similarelements are numbered with the same reference numerals with respect toFIG. 1. Also, in FIG. 12, as for the image forming apparatus 1, only theimage read-out means 12 and the IDT 13 are illustrated.

[0110] With reference to FIG. 12, in an image processing apparatus 202,a plurality of marker signals M, M, . . . , which represent markerpatterns having different sizes and having been prepared previously, arestored in the memory 21. Also, selection means 26 selects a markersignal M representing a marker pattern having a size adapting to thesize of the image, which is represented by the image signal S0, and/orthe read-out density, with which the image signal S0 was obtained. Theselection is made from the plurality of the marker signals M, M, . . .of different sizes, which are stored in the memory 21. Further, by theutilization of the selected marker signal M, the determination means 22determines the direction and the appending position of the markerpattern in accordance with the image recording technique. Therefore, theimage signal S0 and/or read-out density information H is fed from theimage read-out means 12 into the selection means 26.

[0111] In the selection means 26, the size of the marker signal M isselected in the manner described below. In this embodiment, it isassumed that the predetermined reference image size and thepredetermined reference read-out density have been set previously.Firstly, selection of the size of the marker signal M in accordance withthe size of the image signal S0 is performed in the manner describedbelow. Specifically, the ratio between the length of the longer side ofthe image, which is represented by the image signal S0, and the lengthof the longer side of the image having the predetermined size iscalculated. In accordance with the calculated ratio, the size of themarker signal M is selected. For example, the image having thepredetermined size may have a 800×600 size, the image represented by theimage signal S0 may have a 1,200×900 size, and the marker pattern, whichis represented by the marker signal M and which adapts to the image ofthe predetermined size, may have a 40×30 size. In such cases, the markersignal M of a size 1.5 times as large as the aforesaid size, i.e. a60×45 size, is selected.

[0112] Selection of the size of the marker signal M in accordance withthe read-out density information H is performed in the manner describedbelow. Specifically, the size of the marker signal M is selected inaccordance with the ratio between the pixel size in the image, which isread out with the predetermined read-out density, and the pixel size inthe image, which is represented by the image signal S0, such that thesize of the marker pattern on the image may be kept as a predeterminedsize regardless of the pixel size. For example, in cases where thepredetermined read-out density is 600 dpi and the read-out density, withwhich the image signal S0 was obtained, is 1,200 dpi, the pixel size inthe image represented by the image signal S0 is one half of the pixelsize in the image, which is read out with the predetermined read-outdensity. Therefore, in cases where the size of the marker patternadapting to the predetermined read-out density is a 40×30 size, themarker signal M of a size two times as large as the aforesaid size, i.e.a 80×60 size, is selected such that the size of the marker pattern maynot be altered on the image represented by the image signal S0.

[0113] In cases where the size of the marker signal M is to be selectedin accordance with both the size of the image, which is represented bythe image signal S0, and the read-out density information H, the size ofthe marker signal M may be selected in accordance with the ratio betweenthe length of the longer side of the image, which is represented by theimage signal S0, and the length of the longer side of the image havingthe predetermined size, and in accordance with the ratio between thepixel size in the image, which is read out with the predeterminedread-out density, and the pixel size in the image, which is representedby the image signal S0.

[0114] How the fifth embodiment of the image processing apparatus inaccordance with the present invention operates will be describedhereinbelow. FIG. 13 is a flow chart showing how the fifth embodiment ofthe image processing apparatus in accordance with the present inventionoperates. Firstly, in steps S31 and S32, as in the steps S1 and S2 inthe first embodiment described above, formation of the image signal S0and the feeding of the ID information T are performed. Also, the imagesignal S0, the ID information T, and the read-out density information Hrepresenting the read-out density, with which the image signal S0 wasobtained, are fed into the image processing apparatus 202. In a stepS33, the selection means 26 of the image processing apparatus 202selects the size of the marker signal M in accordance with the size ofthe image, which is represented by the image signal S0, and/or theread-out density information H. Also, in a step S34, the marker signal Mof the selected size is read from the memory 21, and the direction andthe appending position of the marker signal M are determined inaccordance with the ID information T. In a step S35, the marker signalappending means 23 appends the marker signal M to the image signal S0.

[0115] In steps S36, S37, and S38, as in the steps S5, S6, and S7 in thefirst embodiment described above, the direction transforming process,the image processing, and reproduction of a visible image from theprocessed image signal S2 are performed.

[0116] As described above, with the fifth embodiment, the marker signalM representing the marker pattern having the size adapting to the sizeof the image, which is represented by the image signal S0, and/or theread-out density, with which the image signal S0 was obtained, isselected from a plurality of marker signals M, M, . . . , whichrepresent marker patterns having different sizes and having beenprepared previously in the memory 21 . The selected marker signal M isappended to the image signal S0. Therefore, the marker pattern havingthe size adapting to the size of the image, which is represented by theimage signal S0, and/or the read-out density, with which the imagesignal S0 was obtained, can be displayed on the image. Accordingly, themarker pattern which is easy to see can be obtained.

[0117] As in an image processing apparatus 202′ shown in FIG. 14, whichconstitutes a sixth embodiment, a plurality of marker signals M, M, . .. , which represent marker patterns having different sizes, may bestored in the memory 21 of the image processing apparatus 2′ shown inFIG. 6, and the selection means 26 may be provided. In the selectionmeans 26, the marker signal M representing the marker pattern having thesize adapting to the size of the image, which is represented by theimage signal S0, and/or the read-out density, with which the imagesignal S0 was obtained in the image read-out means 12, may be selectedfrom the plurality of the marker signals M, M, . . . , which representmarker patterns having different sizes and having been stored in thememory 21. Also, in the marker signal altering means 30, by use of theselected marker signal M, the direction of the marker pattern may bedetermined in accordance with the image recording technique.

[0118] In the first to sixth embodiments described above, if the imagesignal components of the image signal S0, which correspond to theposition in the vicinity of the appending position of the marker signalM, take signal values (for example, in the cases of 8 bits, 255 orvalues close to 255) approximately identical with the signal value ofthe marker signal M, the marker pattern will become imperceptible in thereproduced image appended with the marker pattern. Therefore, as in animage processing apparatus 302 shown in FIG. 15, which constitutes aseventh embodiment, signal value altering means 40 should preferably belocated between the direction transforming means 24 and the processingmeans 25. The signal value altering means 40 operates such that, incases where the signal value of the marker signal M and signal values ofimage signal components of the direction-transformed image signal S1,which image signal components correspond to the position in the vicinityof the appending position of the marker signal M, approximately coincidewith each other, the signal value altering means 40 alters the signalvalue of the marker signal M and/or the signal values of the imagesignal components of the direction-transformed image signal S1, whichimage signal components correspond to the position in the vicinity ofthe appending position of the marker signal M.

[0119] By way of example, the signal value altering means 40 calculatesthe difference value between the signal value of the marker signal M andthe signal values of the image signal components of thedirection-transformed image signal S1, which image signal componentscorrespond to the position in the vicinity of the appending position ofthe marker signal M. Also, in cases where the calculated differencevalue is smaller than a predetermined threshold value, the signal valuealtering means 40 alters the signal value of the marker signal M and/orthe signal values of the image signal components of thedirection-transformed image signal S1, which image signal componentscorrespond to the position in the vicinity of the appending position ofthe marker signal M. Specifically, the signal value of the marker signalM may be altered to the inverted values of the signal values of theaforesaid image signal components of the direction-transformed imagesignal S1. Alternatively, the signal value of the marker signal M may bealtered to the values, which are obtained by adding a predeterminedvalue to the signal values of the aforesaid image signal components ofthe direction-transformed image signal S1. As another alternative, thesignal value of the marker signal M may be altered to the values, whichare obtained by subtracting a predetermined value from the signal valuesof the aforesaid image signal components of the direction-transformedimage signal S1. As a further alternative, the signal values of theaforesaid image signal components of the direction-transformed imagesignal S1 may be altered to the inverted value of the signal value ofthe marker signal M. As a still further alternative, the signal valuesof the aforesaid image signal components of the direction-transformedimage signal S1 may be altered to the value, which is obtained by addinga predetermined value to the signal value of the marker signal M. Asanother alternative, the signal values of the aforesaid image signalcomponents of the direction-transformed image signal S1 may be alteredto the value, which is obtained by subtracting a predetermined valuefrom the signal value of the marker signal M. In this manner, the signalvalue of the marker signal M and/or the signal values of the imagesignal components of the direction-transformed image signal S1, whichimage signal components correspond to the position in the vicinity ofthe appending position of the marker signal M, can be altered.

[0120] In the manner described above, with the seventh embodiment ofFIG. 15, in cases where the signal value of the marker signal M andsignal values of image signal components of the direction-transformedimage signal S1, which image signal components correspond to theposition in the vicinity of the appending position of the marker signalM, approximately coincide with each other, the signal value of themarker signal M and/or the signal values of the image signal componentsof the direction-transformed image signal S1, which image signalcomponents correspond to the position in the vicinity of the appendingposition of the marker signal M, are altered. With the seventhembodiment, for example, when a white marker pattern is appended to awhite region in the image, the marker pattern can be kept easy to see.

[0121] In the seventh embodiment of FIG. 15, the signal value alteringmeans 40 is located in the image processing apparatus 2 shown in FIG. 1,which constitutes the first embodiment. In the same manner, the signalvalue altering means 40 may be located in the image processingapparatuses shown in FIGS. 6, 9, 11, 12, and 14, which constitute thesecond to sixth embodiments. In the second, fourth, and sixthembodiments shown in FIGS. 6, 11, and 14, the signal value alteringmeans 40 may be located between the marker signal appending means 23′and the processing means 25′.

[0122] In the embodiments described above, the marker signal M isappended to the image signal S0 at the time at which the image signal S0is reversed. By way of example, in cases where a radiation image of apatient having a comparatively large body is to be recorded on thestimulable phosphor sheet 17, the image recording operation is oftenperformed, wherein the stimulable phosphor sheet 17 is rotated by anangle of 90 degrees, and a radiation image of a portion of the patientextending over a range in the horizontal direction, which range isbroader than the range in the vertical direction, is recorded. In caseswhere the image recording operation is performed in this manner, in theimage read-out means 12, the stimulable phosphor sheet 17 is conveyedalong its longitudinal direction, and the radiation image stored on thestimulable phosphor sheet 17 is read out. Therefore, when a visibleimage is reproduced directly from the thus detected image signal S0, aradiation image as shown in FIG. 16A is obtained. At this time, the IDinformation T contains the information representing that the stimulablephosphor sheet 17 was orientated with its longitudinal side extendinghorizontally in the image recording operation. Therefore, in thedirection transforming means 24 or 24′, the direction transformingprocess is performed on the image signal S0, in which the radiationimage represented by the image signal S0 is rotated counter-clockwise byan angle of 90 degrees and is thereafter reversed. From the directiontransforming process, the direction-transformed image signal S1 isobtained, from which an image shown in FIG. 16B can be reproduced.

[0123] In such an image recording operation, an L-shaped marker may beattached to a position on the stimulable phosphor sheet 17, whichposition corresponds to a position in the vicinity of the left shoulderof the patient. In such cases, as illustrated in FIG. 17A, an L-shapedmarker pattern is embedded in the image represented by the image signalS0. Also, as illustrated in FIG. 17B, in the image represented by thedirection-transformed image signal S1, which is obtained from theprocess performed by the direction transforming means 24 or 24′ on theimage signal S0 for rotating the image counter-clockwise by an angle of90 degrees and then reversing the right and left sides of the image, themarker pattern having the rotated and reversed L-shape is embedded.Therefore, the medical doctor, who sees the image shown in FIG. 17B, canconfirm that the marker pattern has been rotated and reversed, and canthereby recognize that the entire image has been rotated and reversed.

[0124] Accordingly, in the determination means 22 in the first, third,and fifth embodiments, which are shown in FIGS. 1, 9, and 12, thedirection and the appending position of the marker signal M aredetermined such that, when the image signal S0 is rotated and reversedby the direction transforming means 24, the image as shown in FIG. 17Bcan be obtained, in which the marker pattern having the rotated andreversed L-shape is embedded. Also, the marker signal appending means 23appends the marker signal M to the image signal S0 in accordance withthe thus determined direction and the thus determined appending positionof the marker signal M. Specifically, as illustrated in FIG. 18, themarker signal M is appended to the image signal S0 such that theL-shaped marker pattern, marker signal M is appended to the image signalS0 such that the L-shaped marker pattern, which is represented by themarker signal M, is rotated clockwise by an angle of 90 degrees andembedded in the thus rotated, non-reversed form at a position in thevicinity of the image pattern of the left shoulder of the patient in theimage represented by the image signal S0. In this manner, the markersignal M is appended to the image signal S0. Therefore, as illustratedin FIG. 17B, when a visible image is reproduced from the direction transformed image signal S1, which has been obtained by rotating andreversing the image represented by the image signal S0 having beenappended with the marker signal M, the reproduced image can be obtainedin the same manner as that in the cases where the image recordingoperation was performed by use of a marker.

[0125] In the marker signal altering means 30 in the second, fourth, andsixth embodiments, which are shown in FIGS. 6, 11, and 14, the directionof the marker signal M is altered and the direction-altered markersignal M′ is obtained such that, when the image signal S0 is rotated andreversed by the direction transforming means 24′, the image as shown inFIG. 17B can be obtained, in which the marker pattern having the rotatedand reversed L-shape is embedded. In this manner, the direction-alteredmarker signal M′ is appended to the image signal S10. Therefore, asillustrated in FIG. 17B, when a visible image is reproduced from theimage signal S11 having been appended with the direction-altered markersignal M′, the reproduced image can be obtained in the same manner asthat in the cases where the image recording operation was performed byuse of a marker.

[0126] In the first, third, and fifth embodiments, which are shown inFIGS. 1, 9, and 12, after the marker signal M has been appended to theimage signal S0, the direction transforming process is performed.Alternatively, the direction transforming process may be performed onthe image signal S0 before being appended with the marker signal M, andthe direction-transformed image signal S1 may thereby be obtained.Thereafter, in accordance with the direction and the appending positionof the marker signal M, which have been determined in accordance withthe information giving specifics about the image recording technique,the marker signal M may be appended to the direction-transformed imagesignal S1.

What is claimed is:
 1. An image processing method, in which a directiontransforming process is performed on an image signal representing animage and in accordance with information giving specifics about an imagerecording technique, and in which a marker pattern represented by amarker signal is appended to the image represented by the image signal,the method comprising the steps of: i) determining a direction of themarker signal and an appending position of the marker signal inaccordance with the information giving specifics about the imagerecording technique, and ii) appending the marker signal to the imagesignal in accordance with the thus determined direction of the markersignal and the thus determined appending position of the marker signal.2. A method as defined in claim 1 wherein a size of the marker signal isaltered in accordance with a size of the image, which is represented bythe image signal, and/or a read-out density, with which the image signalwas obtained.
 3. A method as defined in claim 1 wherein a marker signalrepresenting a marker pattern having a size adapting to a size of theimage, which is represented by the image signal, and/or a read-outdensity, with which the image signal was obtained, is selected from aplurality of marker signals, which represent marker patterns havingdifferent sizes and having been prepared previously, and the directionand the appending position of the thus selected marker signal aredetermined.
 4. A method as defined in claim 1 or 3 wherein, in caseswhere a signal value of the marker signal and signal values of imagesignal components of the image signal, which image signal componentscorrespond to the position in the vicinity of the appending position ofthe marker signal, approximately coincide with each other, the signalvalue of the marker signal and/or the signal values of the image signalcomponents of the image signal, which image signal components correspondto the position in the vicinity of the appending position of the markersignal, are altered.
 5. An image processing method, in which a directiontransforming process is performed on an image signal representing animage and in accordance with information giving specifics about an imagerecording technique, and in which a marker pattern represented by amarker signal is appended to the image represented by the image signal,the method comprising the steps of: i) performing the directiontransforming process on the image signal, ii) displaying an image, whichis represented by the image signal having been subjected to thedirection transforming process, together with a pointer, which indicatesan arbitrary position on the image, on displaying means, iii) alteringthe direction of the marker signal in accordance with the informationgiving specifics about the image recording technique, iv) altering theshape of the pointer to a shape of a marker pattern, which isrepresented by the altered marker signal, v) altering the position ofthe marker pattern on the image in accordance with a pointer positionaltering instruction, and vi) appending the marker signal to the imagesignal in accordance with a marker pattern appending instruction givenat a desired position on the image displayed on the displaying means. 6.A method as defined in claim 5 wherein a size of the marker signal isaltered in accordance with a size of the image, which is represented bythe image signal, and/or a read-out density, with which the image signalwas obtained.
 7. A method as defined in claim 5 wherein a marker signalrepresenting a marker pattern having a size adapting to a size of theimage, which is represented by the image signal, and/or a read-outdensity, with which the image signal was obtained, is selected from aplurality of marker signals, which represent marker patterns havingdifferent sizes and having been prepared previously, and the directionof the thus selected marker signal is altered.
 8. A method as defined inclaim 5 or 7 wherein, in cases where a signal value of the marker signaland signal values of image signal components of the image signal, whichimage signal components correspond to the position in the vicinity ofthe appending position of the marker signal, approximately coincide witheach other, the signal value of the marker signal and/or the signalvalues of the image signal components of the image signal, which imagesignal components correspond to the position in the vicinity of theappending position of the marker signal, are altered.
 9. An imageprocessing apparatus, which is provided with direction transformingmeans for performing a direction transforming process on an image signalrepresenting an image and in accordance with information givingspecifics about an image recording technique, and in which a markerpattern represented by a marker signal is appended to the imagerepresented by the image signal, the apparatus comprising: i)determination means for determining a direction of the marker signal andan appending position of the marker signal in accordance with theinformation giving specifics about the image recording technique, andii) marker signal appending means for appending the marker signal to theimage signal in accordance with the thus determined direction of themarker signal and the thus determined appending position of the markersignal.
 10. An apparatus as defined in claim 9 wherein the determinationmeans alters a size of the marker signal in accordance with a size ofthe image, which is represented by the image signal, and/or a read-outdensity, with which the image signal was obtained.
 11. An apparatus asdefined in claim 9 wherein the apparatus further comprises storage meansfor storing a plurality of marker signals, which represent markerpatterns having different sizes and having been prepared previously, andselection means for selecting a marker signal representing a markerpattern having a size adapting to a size of the image, which isrepresented by the image signal, and/or a read-out density, with whichthe image signal was obtained, the selection being made from theplurality of the marker signals, which represent the marker patternshaving different sizes and have been stored in the storage means, andthe determination means determines the direction and the appendingposition of the thus selected marker signal.
 12. An apparatus as definedin claim 9 or 11 further comprising signal value altering means foroperating such that, in cases where a signal value of the marker signaland signal values of image signal components of the image signal, whichimage signal components correspond to the position in the vicinity ofthe appending position of the marker signal, approximately coincide witheach other, the signal value altering means alters the signal value ofthe marker signal and/or the signal values of the image signalcomponents of the image signal, which image signal components correspondto the position in the vicinity of the appending position of the markersignal.
 13. An image processing apparatus, which is provided withdirection transforming means for performing a direction transformingprocess on an image signal representing an image and in accordance withinformation giving specifics about an image recording technique, theapparatus comprising: i) displaying means for displaying an image, whichis represented by the image signal having been subjected to thedirection transforming process performed by the direction transformingmeans, together with a pointer, which indicates an arbitrary position onthe image, ii) marker signal altering means for altering a direction ofa marker signal, which represents a marker pattern to be appended to theimage represented by the image signal, in accordance with theinformation giving specifics about the image recording technique, iii)pointer altering means for altering the shape of the pointer to a shapeof a marker pattern, which is represented by the altered marker signal,iv) position altering means for altering the position of the markerpattern on the image in accordance with a pointer position alteringinstruction, and v) marker signal appending means for appending themarker signal to the image signal in accordance with a marker patternappending instruction given at a desired position on the image displayedon the displaying means.
 14. An apparatus as defined in claim 13 whereinthe determination means alters a size of the marker signal in accordancewith a size of the image, which is represented by the image signal,and/or a read-out density, with which the image signal was obtained. 15.An apparatus as defined in claim 13 wherein the apparatus furthercomprises storage means for storing a plurality of marker signals, whichrepresent marker patterns having different sizes and having beenprepared previously, and selection means for selecting a marker signalrepresenting a marker pattern having a size adapting to a size of theimage, which is represented by the image signal, and/or a read-outdensity, with which the image signal was obtained, the selection beingmade from the plurality of the marker signals, which represent themarker patterns having different sizes and have been stored in thestorage means, and the marker signal altering means alters the directionof the thus selected marker signal.
 16. An apparatus as defined in claim13 or 15 further comprising signal value altering means for operatingsuch that, in cases where a signal value of the marker signal and signalvalues of image signal components of the image signal, which imagesignal components correspond to the position in the vicinity of theappending position of the marker signal, approximately coincide witheach other, the signal value altering means alters the signal value ofthe marker signal and/or the signal values of the image signalcomponents of the image signal, which image signal components correspondto the position in the vicinity of the appending position of the markersignal.
 17. A recording medium, on which a program for causing acomputer to execute an image processing method has been recorded andfrom which the computer is capable of reading the program, the imageprocessing method comprising performing a direction transforming processon an image signal representing an image and in accordance withinformation giving specifics about an image recording technique, andappending a marker pattern represented by a marker signal to the imagerepresented by the image signal, wherein the program comprises theprocedures for: i) determining a direction of the marker signal and anappending position of the marker signal in accordance with theinformation giving specifics about the image recording technique, andii) appending the marker signal to the image signal in accordance withthe thus determined direction of the marker signal and the thusdetermined appending position of the marker signal.
 18. A recordingmedium as defined in claim 17 wherein the program further comprises theprocedure for altering a size of the marker signal in accordance with asize of the image, which is represented by the image signal, and/or aread-out density, with which the image signal was obtained.
 19. Arecording medium as defined in claim 17 wherein the program furthercomprises the procedure for selecting a marker signal representing amarker pattern having a size adapting to a size of the image, which isrepresented by the image signal, and/or a read-out density, with whichthe image signal was obtained, the selection being made from a pluralityof marker signals, which represent marker patterns having differentsizes and having been prepared previously, and the procedure for thedetermination is a procedure for determining the direction and theappending position of the thus selected marker signal.
 20. A recordingmedium as defined in claim 17 or 19 wherein the program furthercomprises the procedure for operating such that, in cases where a signalvalue of the marker signal and signal values of image signal componentsof the image signal, which image signal components correspond to theposition in the vicinity of the appending position of the marker signal,approximately coincide with each other, the signal value of the markersignal and/or the signal values of the image signal components of theimage signal, which image signal components correspond to the positionin the vicinity of the appending position of the marker signal, arealtered.
 21. A recording medium, on which a program for causing acomputer to execute an image processing method has been recorded andfrom which the computer is capable of reading the program, the imageprocessing method comprising performing a direction transforming processon an image signal representing an image and in accordance withinformation giving specifics about an image recording technique, andappending a marker pattern represented by a marker signal to the imagerepresented by the image signal, wherein the program comprises theprocedures for: i) performing the direction transforming process on theimage signal, ii) displaying an image, which is represented by the imagesignal having been subjected to the direction transforming process,together with a pointer, which indicates an arbitrary position on theimage, on displaying means, iii) altering the direction of the markersignal in accordance with the information giving specifics about theimage recording technique, iv) altering the shape of the pointer to ashape of a marker pattern, which is represented by the altered markersignal, v) altering the position of the marker pattern on the image inaccordance with a pointer position altering instruction, and vi)appending the marker signal to the image signal in accordance with amarker pattern appending instruction given at a desired position on theimage displayed on the displaying means.
 22. A recording medium asdefined in claim 21 wherein the program further comprises the procedurefor altering a size of the marker signal in accordance with a size ofthe image, which is represented by the image signal, and/or a read-outdensity, with which the image signal was obtained.
 23. A recordingmedium as defined in claim 21 wherein the program further comprises theprocedure for selecting a marker signal representing a marker patternhaving a size adapting to a size of the image, which is represented bythe image signal, and/or a read-out density, with which the image signalwas obtained, the selection being made from a plurality of markersignals, which represent marker patterns having different sizes andhaving been prepared previously, and the procedure for altering thedirection of the marker signal is a procedure for altering the directionof the thus selected marker signal.
 24. A recording medium as defined inclaim 21 or 23 wherein the program further comprises the procedure foroperating such that, in cases where a signal value of the marker signaland signal values of image signal components of the image signal, whichimage signal components correspond to the position in the vicinity ofthe appending position of the marker signal, approximately coincide witheach other, the signal value of the marker signal and/or the signalvalues of the image signal components of the image signal, which imagesignal components correspond to the position in the vicinity of theappending position of the marker signal, are altered.
 25. An imageprocessing method according to claim 1, wherein said image signalrepresenting an image is an output of an image read out device obtainingsignal information from a recording medium.
 26. An image processingmethod according to claim 25, wherein said image signal representing animage is irradiated from a stimulable phosphor sheet.
 27. An imageprocessing method according to claim 1, wherein the directiontransforming process comprises a process for reversing and/or rotatingthe image signal, wherein an image seen from a desired direction can beobtained when an image is reproduced from the image signal having beenobtained from the process.
 28. An image processing method according toclaim 27, wherein rotating the image signal comprises an operation forrotating the image, which is represented by the image signal, by desiredangle around the center of gravity of an image.
 29. An image processingmethod according to claim 27, wherein reversing comprises an operationfor reversing the image, which is represented by the image signal,symmetrically with respect to an axis.
 30. An image processing methodaccording to claim 1, wherein appending a marker signal to an imagesignal comprises replacing the image signal components of the imagesignal, which correspond to the position to be appended with the markerpattern, by the marker signal.
 31. An image processing method accordingto claim 1, wherein appending a marker signal to an image signalcomprises appending the marker signal to the image signal as an overlaysignal for the image signal.
 32. An image processing method according toclaim 2, wherein the marker signal is altered according to the ratiobetween the length of the longer side of an image, which is representedby the image signal, and the length of the longer side of the imagehaving a predetermined size.
 33. An image processing method according toclaim 2, wherein the marker signal is altered by adding a predeterminedvalue to the signal values of said image signal components of thedirection-transformed image signal.
 34. An image processing methodaccording to claim 1, wherein the marker signal is appended to the imagesignal according to information giving specifics about an imagerecording technique from an identification terminal, wherein saididentification terminal provides information to a determination meanswhich determines a direction of the marker signal and an appendingposition of the marker signal in accordance with the information fromthe identification terminal, and the determination means is providedwith a marker signal which is stored in a memory.
 35. An imageprocessing method according to claim 1, wherein the marker signal isappended to the image signal according to information giving specificsabout an image recording technique, wherein said information is used todetermine a direction of the marker signal and an appending position ofthe marker signal in accordance with said information, and thedetermination means is provided with a marker signal which is stored ina memory.